scholarly journals Wood and bark fiber characteristics of Acacia melanoxylon and comparison to Eucalyptus globules

CERNE ◽  
2011 ◽  
Vol 17 (1) ◽  
pp. 61-68 ◽  
Author(s):  
Fatima Tavares ◽  
Teresa Quilhó ◽  
Helena Pereira

Wood and bark fibers of Acacia melanoxylon were characterized and compared to Eucalyptus globulus which is a major quality source of pulp fibers. In 20 trees from four sites, fiber length and wall thickness were measured at 5, 35 and 65% of total tree height and at 10, 30, 50, 70 and 90% of the distance from pith. Maceration were prepared in a 1:1 glacial acetic acid:hydrogen peroxide solution. Wood and bark fiber length varied between 0.90 - 0.96 mm and 1.33 - 1.59 mm respectively. The cell wall thickness varied between 3.45 - 3.89 µm in wood and 5.01 - 5.40 µm in bark. Wood and bark fiber length decreased from the bottom to the top of the tree and cell wall thickness had no specific pattern for axial variation. Fiber length and wall thickness increased from the pith to the bark, but the wall thickness increased slightly with some fluctuations. In Acacia melanoxylon significant site differences were found in relation to bark fiber length and to wood wall thickness. The fibers of Acacia melanoxylon were similar to those of Eucalyptus globulus but the wood fibers were thinner and the bark fibers thicker. The radial variation was similar in both species. In wood of Eucalyptus globulus, fiber wall thickness increases from the base to the middle of tree height and decreases to the top; in the bark decreases from the base to the top. In Eucalyptus globulus fibers bark are higher in the top.

2019 ◽  
Vol 28 (2) ◽  
pp. e011 ◽  
Author(s):  
Majid Kiaei ◽  
Valiullah Moosavi ◽  
Seyed Eshagh Ebadi

Aim of the study: This study aimed to investigate the effect of altitude difference on the wood dry density, fiber dimensions, and morphological properties of hornbeam wood (Carpinus betulus L.).Area of study: The study area was located in the province of Mazandaran, north of Iran.Material and method: 18 mature trees were randomly selected and harvested at six altitude levels (300, 500, 700, 900, 1100, and 1300 m) in the north of Iran. The clear test samples‎ were prepared‎ at diameter at breast height (DBH) to measure the wood dry density, fiber length, fiber diameter, cell wall thickness, Runkel coefficients, flexibility coefficients, and slenderness coefficients. Further ‎analyses included the relationships between the wood properties and site conditions (temperature, ‎precipitation, crown canopy, ‎and understory herb layer) as well as tree’s main dimensions ‎(tree height and the DBH).Main results: The results indicated significant effects of altitude variations on the studied ‎properties. The pattern variations of wood properties were very regular at different levels of height. The average fiber length and fiber diameter decreased while the wood dry density and cell wall thickness increased with increasing the altitude levels. The average values of wood dry density, fiber length, fiber diameter, cell wall thickness, slenderness coefficients, flexibility coefficients, and Runkel coefficients of hornbeam wood were 698 kg/m3, 1.42mm, 25.58 µm, 5.72µm, 55.55, 54.04%, and 0.93, respectively, in the above six altitudes. Pearson matrix correlation showed that there were significant relationships between temperature, crown canopy, tree height and DBH ‎with the studied wood properties (except the slenderness coefficients)‎.Research highlights: The hornbeams grown at altitudes above 900-1300 m were not suitable for pulp and ‎paper production‎ due to relatively higher Runkel coefficients, the lower flexibility coefficients, as well as smaller fiber length than other altitude levels.Additional Keywords: Carpinus betulus; altitude variation; density; fiber dimensions; morphological properties.Abbreviations used: WDD (wood dry density); FL (fiber length); FD (fiber diameter), CWT (cell wall thickness); FC (flexibility coefficient); RC (Runkel coefficients); SC (slenderness coefficient).


BioResources ◽  
2020 ◽  
Vol 15 (3) ◽  
pp. 5696-5709
Author(s):  
Ali Hassanpoor Tichi ◽  
Habibollah Khademieslam ◽  
Mojtaba Rezanezhad Divkolae

Three healthy Citrus sinensis (orange) trees in Babol, Iran, were randomly selected and cut. Two discs of 5 cm thickness were prepared along the tree (breast height and crown). In the transverse direction, the test specimens were cut 2 × 2 cm to 3 cm from the pith to the bark sequentially and examined. The biometric and physical properties were measured, and microscopic sections of wood near the bark were studied using light microscopy according to the International Association of Wood Anatomists’ (IAWA) List. Anatomical examination of the C. sinensis wood showed that the species was a diffuse porous hardwood, with indistinct growth rings, simple perforation plates, alternate intervessel pits, and banded parenchyma. The basic density and oven-dry density increased from the pith towards the tree bark and from the bottom of the tree towards the crown. There was a significant difference in both the transverse and longitudinal directions of the C. sinensis tree in terms of fiber length, fiber lumen diameter, fiber diameter, and cell wall thickness. The mean fiber length, fiber diameter, fiber lumen diameter, and cell wall thickness were 0.76 mm, 23.64 µm, 9.23 µm, and 14.41 µm, respectively.


IAWA Journal ◽  
2009 ◽  
Vol 30 (3) ◽  
pp. 343-352 ◽  
Author(s):  
F. Ishiguri ◽  
T. Hiraiwa ◽  
K. Iizuka ◽  
S. Yokota ◽  
D. Priadi ◽  
...  

Radial variation in anatomical characteristics of five 13-year-old Paraserianthes falcataria (L.) Nielsen (syn. Albizia falcataria (L.) Fosberg), an important commercial tree species in Indonesia, were investigated in order to obtain basic information regarding breeding for wood quality. Both cell wall thickness in wood fibers and vessel percentage showed an almost constant value up to 10 cm from the pith and then increased toward the bark. In contrast, wood fiber percentage decreased from 10 cm toward the bark. The cell wall percentage was lower towards the pith and higher towards the bark. In the five sample trees, significant differences were found in the cell diameter of wood fibers, wood fiber percentage, axial parenchyma percentage, and cell wall percentage. Basic density was affected by the cell wall thickness of wood fibers, but not the vessel percentage and fiber percentage.


2014 ◽  
Vol 11 (1) ◽  
pp. 51
Author(s):  
Mohd Helmy Ibrahim ◽  
Mohd Nazip Suratman ◽  
Razali Abd Kader

Trees planted from agroforestry practices can become valuable resources in meeting the wood requirements of many nations. Gliricidia sepium is an exotic species introduced to the agricultural sector in Malaysia mainly for providing shade for cocoa and coffee plantations. This study investigates its wood physical properties (specific gravity and moisture content) and fibre morphology (length, lumen diameter and cell wall thickness) of G. sepium at three intervals according to age groups ( three, five and seven years of ages). Specific gravity (0.72) was significantly higher at seven years ofage as compared to five (0.41) and three (0.35) years age group with a mean of 0.43 (p<0.05). Mean moisture content was 58.3% with no significant difference existing between the tree age groups. Fibre diameter (22.4 mm) was significantly lower (p<0.05) for the trees which were three years of age when compared to five and seven years age groups (26.6 mm and 24. 7 mm), respectively. Means of fibre length, lumen diameter and cell wall thickness were 0.83 mm, 18.3 mm, and 6.2 mm, respectively, with no significant differences detected between trees in all age groups. Further calculation on the coefficient of suppleness and runkel ratio suggest that wood from G.sepium may have the potential for insulation board manufacturing and paper making. However, future studies should experiment the utilisation of this species for these products to determine its full potential.


2021 ◽  
pp. 026248932110068
Author(s):  
Youming Chen ◽  
Raj Das ◽  
Hui Wang ◽  
Mark Battley

In this study, the microstructure of a SAN foam was imaged using a micro-CT scanner. Through image processing and analysis, variations in density, cell wall thickness and cell size in the foam were quantitatively explored. It is found that cells in the foam are not elongated in the thickness (or rise) direction of foam sheets, but rather equiaxed. Cell walls in the foam are significantly straight. Density, cell size and cell wall thickness all vary along the thickness direction of foam sheets. The low density in the vicinity of one face of foam sheets leads to low compressive stiffness and strength, resulting in the strain localization observed in our previous compressive tests. For M80, large open cells on the top face of foam sheets are likely to buckle in compressive tests, therefore being another potential contributor to the strain localization as well. The average cell wall thickness measured from 2D slice images is around 1.4 times that measured from 3D images, and the average cell size measured from 2D slice images is about 13.8% smaller than that measured from 3D images. The dispersions of cell wall thickness measured from 2D slice images are 1.16–1.20 times those measured from 3D images. The dispersions of cell size measured from 2D slice images are 1.12–1.36 times those measured from 3D images.


2003 ◽  
Vol 33 (10) ◽  
pp. 1905-1914 ◽  
Author(s):  
Irina P Panyushkina ◽  
Malcolm K Hughes ◽  
Eugene A Vaganov ◽  
Martin AR Munro

We reconstructed air temperature for two periods in the growth season from cell dimension and cell number variability in cross-dated tree rings of Larix cajanderi Mayr. from northeastern Siberia. Thirteen tree-ring chronologies based on cell size, cell wall thickness, and cell number were developed for AD 1642–1993. No clear evidence was found of an age-related trend in cell dimensions in the sampled materials, but cell numbers were correlated with cambial age. The chronologies contain strong temperature signals associated with the timing of xylem growth. We obtained reliable reconstructions of mean June temperature from the total cell number and July–September temperature from the cell wall thickness of latewood. June temperature and July–September temperature covaried for most of the period from AD 1642 to AD 1978. After that time, June temperature became cooler relative to July–September temperature. This difference caused disproportional changes in earlywood tracheids because of the late start of growth and cool conditions in June followed by warming during the rest of the season. The identification of this unusual recent change has shown that intraseasonal resolution may be achieved by cell dimension and cell number chronologies.


IAWA Journal ◽  
2000 ◽  
Vol 21 (1) ◽  
pp. 31-40 ◽  
Author(s):  
Teresa Quilhó ◽  
Helena Pereira ◽  
Hans Georg Richter

The axial variation of bark thickness and quantitative anatomical features of Eucalyptus globulus bark were analysed for one site based on individual measurements of ten 15-year-old trees at six height levels (DBH, 5%, 15%, 35%, 55% and 75% of total tree height). The parameters studied were: length, tangential diameter and percentage of sieve tubes; length, width, cell wall thickness and percentage of fibres; height and percentage of rays; percentage of sclereids in the secondary phloem. Bark thickness decreases from base to top of the tree. Fibre width and wall thickness decrease from base upwards. No distinct axial patterns of variation were observed for the other biometric variables studied. Parenchyma is the main cell type of the bark (50%) followed by fibres (27.9%), rays (12.1%), sieve tubes (2.7%), and sclereids (7.3%). The cell type proportions vary significantly within the tree, i.e., parenchyma, ray and sclereid proportions decrease, fibre and sieve tube proportions increase towards the top of the tree.


2001 ◽  
Vol 31 (11) ◽  
pp. 2049-2057 ◽  
Author(s):  
Tongli Wang ◽  
Sally N Aitken

Variation in xylem anatomy among selected populations of lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) was examined using digital image analysis based on an annual growth ring (age 10) per tree. Four subpopulations were selected using the following criteria for height growth and wood density: (i) fast growth and high density; (ii) slow growth and high density; (iii) fast growth and low density; and (iv) slow growth and low density. Significant differences were found among subpopulations for several anatomical parameters including tracheid density, lumen size, and cell wall thickness that may affect the economic value and utilization of wood. Principal component analysis indicate that the first four principal components (PCs) were associated with (i) ring area (PC1), (ii) earlywood density (PC2), (iii) latewood density (PC3), and (iv) lumen shape in earlywood (PC4), suggesting that these aspects of wood properties and growth are controlled by different sets of genes. Relative contributions of total number of tracheids, tracheid lumen size, and cell wall thickness to ring area and correlations between cell wall area proportion and X-ray density are discussed.


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